I'm having a problem with my audio tracks. When I opened up my file that I have been working on, the tracks are missing but the clip size is still there. It's like I selected a time frame to record but it didn't go through, however it was there yesterday. I saved my file so that shouldn't be the problem, so what is?

I found out that I can put the samples from the project folder into the Bitwig DAW. I did not know you could do that. I guess I'll have to start over, but at least I didn't lose the audio tracks that I recorded. So I guess I solved my problem.

[This works on windows, but probably also on other systems]
DO A COPY OF YOUR PROJECT FIRST
Open your bitwig project file using notepad and using the find tool ( Edit>Find) search for the name of your audio file that was missing (for example "Filename.wav" without the quotation marks). After some time you will find a path containing your audio file name (like "C:/Users/Filename.wav"). This means that your original audio file was on that location and that you have to put a copy of your original audio file in that path with that exact name in order to make it work properly again.
Close notepad without saving and after you followed the instructions above it should work.

If then you want to move your audio file location so that nothing like this will happen again I think the only way is to bounce your clip in bitwig so that bitwig will save it automatically in your project folder.

Do not try editing your file with notepad because changing even only the path will result into a damaged project that won't work anymore.